Most likely asked 10,000 times before but we are in Australia, on a budget. I'm building a 383/431 for my wifes 67 Dart, nothing to radical but 11.3 to 1 with sidewinders and a Engle 585 603 flat tap solid, 750dp on an m1 with an msd 6 digital, ol hooker fender exits, J converter with a shift kit, Ive got a 741 case on my 8 3/4, currently 3.23 gears with a lsd. not going drag radials or anything like that & I know the gears are wrong for that cam and converter but I'm looking at 3.7s or similar. My wife likes to race a little so I'm hoping the 741 case will handle it. your thoughts?

If the car does not spin and then hook that rear end will be fine
I raced my 1969 Dart GTS with the same third member with 3.91 gears and posi with a 440 with a 727 that ran low elevens for many, many runs and it is still in the car running today with the 383 motor and 4 speed 833 NP tranny back in it

741 case?

As 9 sec. Phil told me "you're more likely to break an axle than that pinion". I haven't broken one during normal operation or the occasional drag race. Like the above post noted. Spinning and catching is harder on them.

I ran one in my 4,200 pound Charger for years. Did not have a problem till I got into the high 11's, and then the limited slip started making noise, but other than that it was OK.

I ran the 742 forever w/a spool and it never broke even in the 1.3 60's and in the 9's in the 1/4 mile but not too sure on the 741 but would agree that it SHOULD hold up................

Ok cool, this 8 7.5 has 30 spline Yukon axles.

Dr. Diff has a very good comparison on his website:

http://www.doctordiff.com/blog/tech-info/rearend-pinion-comparison/